Horizontal continuous casting apparatus with reciprocatory gate

ABSTRACT

In apparatus for the continuous horizontal casting of metals, which comprises a vessel communicating through a lateral orifice located in the vicinity of the bottom thereof with the inlet end of an ingot mold, from which the molded product is removed substantially continuously, a reciprocatory gate is provided for closing the vessel orifice and cutting of passage of the molten metal from the orifice into the mold.

United States Patent 1191 Antoine et al.

14 1 Sept. 9, 1975 HORIZONTAL CONTINUOUS CASTING APPARATUS WITHRECIPROCATORY GATE [75] Inventors: Jacques Antoine,

Longeville-les-Metz; Robert Alberny; Jacques Michelet, both of Metz, allof France [73] Assignee: Institut de Recherches de la SiderurgieFrancaise (IRSID), St. Germain-en-Laye, France [22] Filed: Oct. 26, 1973[21] Appl. No.: 410,293

[30] Foreign Application Priority Data Nov. 6, 1972 France 72.39113 [52]US. Cl 164/281; 164/259 [51] Int. Cl B22d 11/10 [58] Field of Search164/82, 281, 282; 222/DIG. 7

[56] References Cited UNITED STATES PATENTS 311,902 2/1885 Lewis 222 512x 3,685,705 8/1972 Cessna 222/561 x FOREIGN PATENTS OR APPLICATIONS239,979 5 1965 Austria 164/281 Primary Examiner-Robert D. BaldwinAttorney, Agent, or FirmKurt Kelman [57] ABSTRACT In apparatus for thecontinuous horizontal casting of metals, which comprises a vesselcommunicating through a lateral orifice located in the vicinity of thebottom thereof with the inlet end of an ingot mold,

from which the molded product is removed substantially continuously, areciprocatory gate is provided for closing the vessel orifice andcutting of passage of the molten metal from the orifice into the mold.

2 Claims, 2 Drawing Figures HORIZONTAL CONTINUOUS CASTING APPARATUS WITHRECIPROCATORY GATE The present invention relates to apparatus for thecontinuous horizontal casting of metals, which term includes metalalloys, especially ferrous alloys such as steel.

Apparatus for the continuous horizontal casting of metals generallycomprises a vessel adapted to receive the metal in the molten statedefining in the vicinity of its lower end a lateral orifice locatedadjacent and in communication with an open-ended ingot mold the form ofwhich determines the cross-section of the case product. Generally, thecast product is extracted from the mold by mechanical means, passage ofthe molten metal from the vessel to the mold taking place most oftenthrough a refractory conduit integral with a wall of the vessel andpenetrating into said mold at one of the ends of the latter.

When carrying out continuous horizontal casting operations, casting mustbe temporarily interrupted while the vessel contains molten metal,whenever the ingot mold must be replaced in order to change thecrosssection of the cast product, or for some other reason, for examplerepair of the ingot mold. Preliminary emptying of the vessel must thenbe carried out and this leads to a drop in the total output of theapparatus. Furthermore, fortuitous tap-holes may come into beingdownstream of the vessel, all of the molten metal contained in thevessel then running out by gravity, the contingency possibly involvingserious disturbances in the casting shop.

The object of this invention is to provide improvements in suchapparatus, especially in regard to the constructive arrangements of therefractory conduit connecting the vessel to the ingot mold, with a viewto improving the conditions in which the apparatus is used insteelworks.

According to the invention, we provide in an apparatus for thecontinuous horizontal casting of metals, which comprises a vesselcommunicating through a lateral orifice located in the vicinity of itslower end with an ingot mold from which the molded product is removedsubstantially continuously, a member for closing the vessel orifice andlocated upstream of the mold relative to the direction in which theproduct is extracted.

The apparatus according to the invention enables the molding operationsto be stopped no matter how full the vessel may be and whatever thereason necessitating the stoppage, without involving unwanted emptyingof the vessel. Indeed, the closing member located upstream of the ingotmold enables the supply of molten metal to the mold to be interruptedand, thus, any necessary operation may be undertaken. This confers uponthe molding process flexibility and reliability not heretoforeobtainable with existing procedures.

The present invention will be better understood on reading the followingdescription given by way of example with reference to a now preferredembodiment illustrated in the accompanying drawing in which:

FIG. 1 is a longitudinal section through a continuous molding apparatusaccording to the invention; and

FIG. 2 is a sectional view through part of the apparatus shown in FIG.1.

In FIG. 1 there is shown a continuous casting apparatus comprisingessentially a reservoir or supply vessel 1 receiving the molten metaland including a lateral orifice 2 located in the side wall close to thebottom of the vessel, this orifice being provided in a nozzle ofrefractory material, and a horizontal ingot mold 4 open at its ends. Theopen inlet end of mold 4 is adjacent and in communication with lateralorifice 2 in vessel 1. The vessel is provided with a device of a typeknown per se for heating and circulating the metal, this deviceincluding channel 26 for circulating and induction heating the metal inthe vessel. Moreover, porous plug 27 is disposed in the bottom of thevessel for insufflation of an inert gas. Besides, the vessel isfurnished with fluid-tight cover 28 so as to enable the establishmentabove the molten metal of a protective atmosphere, the metal beingintroduced into the vessel in a manner known per se through conduit 29which can be closed and is capable of being put in communication with afeed ladle protected from the atmosphere.

The ingot mold may be of any type and is constituted in the illustratedembodiment merely by way of example by a double-walled copper casingassociated with boxes for the introduction and evacuation of a coolingliquid so as to constitute a structure known in the art by the termwater-jacket. The passage of the molten metal from the vessel to theingot mold is effected through connecting conduit 5 which, on the onehand, opens at one end into vessel 1, in axial alignment with lateralorifice 2 and, on the other hand, opens into the open inlet end of theingot mold. In accordance with the invention, the passage of the moltenmetal from the vessel to the ingot mold can be interrupted by a closingdevice described in detail hereinafter.

Referring to FIGS. 1 and 2, connecting conduit 5 is shown as a device 6of a type similar to the devices known as valved nozzles in the art ofcasting of metals, which is interposed between vessei 1 and ingot mold4. The device 6 includes movable closing member or gate 7 guided forreciprocating movement between two fixed plates 8 and 9, the former ofwhich is supported against one of the ends of nozzle 3, and the latterof which is associated with nozzle 10 cooperating with the inlet end ofthe ingot mold in a manner which will be explained hereinafter. Plate 8has a central orifice of the same cross-section as, and co-axial with,lateral orifice 2 and thus makes up a part of connecting conduit 5. Theplate 8 is centered in relation to nozzle 3 and is applied in afluid-tight manner against the latter by a removable metallic clampingplate 11 affixed to vessel 2 by cottering and provided with a bearingsurface 12 cooperating with a peripheral shoulder in plate 8. The plate9 is also provided with a central orifice of the same cross-section as,and co-axial with, lateral orifice 2 and also makes up a part ofconnecting conduit 5. The plate 9 is centered in relation to the lateralorifice by means of a movable metallic clamping plate 13 itself centeredin relation to plate 11 by a machined internal bearing surface 14enabling axial sliding movement in cooperation with a correspondingmachined external bearing surface of fixed clamping plate 11. Themovable plate 13 is provided with a bearing surface 15 cooperating witha peripheral shoulder in plate 9.. The clearance between the twoclamping plates 11 and 13 is regulated by threaded tie rods 16 one endof each of which is fixed to plate 11 and the other ends of which areengaged in bores in the periphery of movable plate 13 and are screwedinto nuts 21.

The movable closing member or gate. "I is of generally parallelipedalshape and is provided with an orifice 17 which can be brought intoalignment with lateral orifice 2 in the vessel by displacement of member7 by the operation of jack 18. The movable member or gate 7 is guidedduring its displacement by metallic guides 19 and 20 integral withclamping plate 1 1 and is displaced in skew notches 30 and 31 made,respectively, in the facing surfaces of plates 8 and 9. The skew notches30 and 31 enable the dimension of the closing member to be reduced inthe direction of the casting and, consequently, the drop in temperatureof the metal while it is passing through connecting conduit 5 to belimited, because of the fact that gate 7 is partially embedded in theplates. The gate 7 is clamped between plates 8 and 9 by tightening nuts21 on threaded tie rods16, with interpositioning of compression springsbetween the nuts and plate 13, the compression force being transmittedby respective bearing surfaces 12 and 15 of plates 11 and 13, so as toenable closing member '7 to be reciprocated while ensuring tightness tothe molten metal between the plates and member 7.

The nozzle 10 has an orifice 22 of the shape of a truncated cone, thesmaller end of which faces towards lateral orifice 2 in the vessel andis of the same crosssection as this orifice, and the larger end of whichfaces towards the ingot mold, being of a cross-section similar to thecross-section of the ingot mold and preferably smaller than the lattercross-section. The nozzle is shaped externally so as to be engaged in arecess 23 of the shape of a truncated cone formed in plate 9 andpresents facing towards the ingot mold a part 24 also of the shape of atruncated cone bearing on a bearing surface of corresponding conicity ofthe ingot mold. The nozzle may be clamped between plate 9 and the ingotmold by the action of a jack 25 held at constant pressure and associatedwith the ingot mold in such a way as to ensure the tightness of theconnecting conduit 5 at the zones where the nozzle 10 is joined,respectively, with plate 9 and with the ingot mold. The ingot mold isguided by slide bars (not shown). The force of application of the ingotmold against nozzle 10 is transmitted by plate 9 to gate 7. it willtherefore be obvious that the clamping force of the plates against thegate is the resultant of the compression force of the springs betweennuts 21 and plate 9, and the force corresponding to the pressure in jack25 when the ingot mold is in the operative position. in the event of theingot mold being detached, the clamping force is produced solely by thecompression springs.

The plates 8 and 9, movable closing member 7 and nozzle 10 are made of arefractory material having rela tively low heat transmissioncharacteristics so as to avoid premature partial solidification inconnecting conduit 5. The selected material may be an aluminousrefractory, zirconium oxide or boron nitride, the'latter material beingparticularly useful for nozzle lit) on account of its very low thermalconductivity and the relatively greater remoteness of this constituentpart of the device in relation to vessel 2. A further advantage of boronnitride is that the molten metal does not wet this material, whichavoids the molten metal being Caught at the inlet to the ingot mold.Other materials having similar properties may, however, be used fornozzle 10.

In the course of a casting operation, the metal is introduced into thevessel in a continuous manner through conduit or pipe 29, it beingpossible to adjust the temperature of the metal in the vessel by meansof induction heating device 26, this device moreover enablingcirculation of the metal to be brought about, which promotes the raisingof embedded materials to the surface; this latter phenomenon isintensified by the bubbling activity induced in the interior of themetal by the insuftlation of an inert gas through porous plug 27,another efiect of this bubbling activity being to make homogenuous thetemperature in the interior of the metal contained in the vessel. Themaintenance of an inert atmosphere above the metal enables the avoidanceof any oxidation of the metal. The product formed in the ingot mold isextracted in a continuous manner at the downstream end of the apparatus,it being possible to vary the speed of extraction cyclically, as isknown in the art.

At the time of an interruption in the casting procedure, closing member7' is displaced so as to cut off the passage of the molten metal fromthe vessel to the ingot mold. After extraction of the metal contained inthe ingot mold and in the part of conduit 5 located between the closingmember and the ingot mold, it is possible to proceed with thedisengagement of the ingot mold through operation of jack 25. it is alsopossible to proceed with the replacement of nozzle 10, either if it isworn out or in order to make its internal shape suitable to the shape ofthe ingot mold when a change in the cross-section of the cast product isdesired. As the metal in conduit 5 is in the molten condition during aperiod while the apparatus is in operation, the shape of thecross-section of this conduit at the end of nozzle 3 in alignment withlateral orifice 2 in the vessel is independent of the shape of thecross-section of the cast product, the transition from one cross-sectionto the other being effected in a progressive manner by orifice 22 innozzle 10. The metal which may be contained in the vessel during thecourse of a period when the casting process is interrupted may bemaintained at a desired temperature as long as is necessary by keepingthe induction heating device in operation, this enabling a subsequentcasting operation to proceed without loss of metal.

What we claim is:

1. in an apparatus for the continuous horizontal casting of a moltenmetal, which comprises a vessel receiving the molten metai, the vesselincluding a bottom and side wall, and the vessel side wall defining alateral orifice in the vicinity of the vessel bottom, a horizontallyextending ingot mold having an open upstream end and an open downstreamend whence a cast metal product is removed, and a means for passing themolten metal from the lateral orifice into the open upstream end of theingot mold, the means comprising a connecting conduit between thelateral orifice and the open upstream end of the ingot mold, and amovable closing gate defining an orifice mounted in the connectingconduit for cutting off passage of the molten metal from the lateralorifice to the ingot mold: the combination of two plates wherebetweenthe gate is held for reciprocating displacement in a directionsubstantially perpendicular to the axis of the lateral orifice, theorifice in the gate having an axis substantially perpendicular to saiddirection and each of the plates having a central orifice coaxialwiththe lateral orifice, one of the plates being affixed to the sidewall of the vessel, with the central orifice thereof in alignment withthe lateral orifice,

the other one of the plates beingmounted for axial glid-v tral orificein the other plate to the open upstream end of the ingot mold.

2. In the apparatus of claim 1, the plates having skew notches, and thegate being of generally parallelipedal shape and being supported in theskew notches for reciprocal displacement.

1. In an apparatus for the continuous horizontal casting of a molten metal, which comprises a vessel receiving the molten metal, the vessel including a bottom and side wall, and the vessel side wall defining a lateral orifice in the vicinity of the vessel bottom, a horizontally extending ingot mold having an open upstream end and an open downstream end whence a cast metal product is removed, and a means for passing the molten metal from the lateral orifice into the open upstream end of the ingot mold, the means comprising a connecting conduit between the lateral orifice and the open upstream end of the ingot mold, and a movable closing gate defining an orifice mounted in the connecting conduit for cutting off passage of the molten metal from the lateral orifice to the ingot mold: the combination of two plates wherebetween the gate is held for reciprocating displacement in a direction substantially perpendicular to the axis of the lateral orifice, the orifice in the gate having an axis substantially perpendicular to said direction and each of the plates having a central orifice coaxial with the lateral orifice, one of the plates being affixed to the side wall of the vessel, with the central orifice thereof in alignment with the lateral orifice, the other one of the plates being mounted for axial gliding movement in respect to the one fixed plate, the other plate having a first bearing surface for centering the other plate in respect of the one plate during the gliding movement, and a nozzle mounted between the other plate and the upstream end of the ingot mold, the other plate having a second bearing surface for centering the nozzle in respect of the other plate, the nozzle having an axial orifice flaring outwardly from the central orifice in the other plate to the open upstream end of the ingot mold.
 2. In the apparatus of claim 1, the plates having skew notches, and the gate being of generally parallelipedal shape and being supported in the skew notches for reciprocal displacement. 